Problem: If $a + b + c = -3$ and $x + y = -9$, what is $-2c - 2a - 3y - 2b - 3x$ ?
Answer: $= -2a - 2b - 2c - 3x - 3y$ $= (-2) \cdot (a + b + c) + (-3) \cdot (x + y)$ $= (-2) \cdot (-3) + (-3) \cdot (-9)$ $= 6 + 27$ $= 33$